In the technology of producing wafers or slices of semiconductor material, a recurring problem is that of shaping the edge of the slices in order to remove the circular protuberances ("epitaxial crowns") which form on the edge of the slices as a result of the growth on them of epitaxial layers and which, unless they are removed, can increase fragility of the slices and pose difficulties in the subsequent diffusion and photomasking operations.
In order to shape the edge and remove the epitaxial crown, currently known equipment carry out mechanical abrasion of the edge by means of diamond wheels or discs of abrasive paper.
This type of equipment, however, has the drawback of producing dust when in operation, and dust notoriously represents a source of contamination for semiconductor layers.